The present invention relates to novel catalysts of metals preferably transition metals and to the processes for using such catalysts for olefin polymerization. The catalyst contains at least one phosphinimine center, and a carbon atom or an alkenyl radical bonded to the metal to form a metal heteroatom alkyl bond or a carbene structure, respectively.
Currently there is increasing interest in catalysts of transition metals having novel structures.
Recently there has been significant interest in Brookhart""s ligand which may complex later transition metals to form a catalyst useful in an olefin polymerization process. Such complexes are disclosed, for example in World Patent Application 96/23010 jointly in the names of the University of Carolina at Chapel Hill and E. I. DuPont published Aug. 1, 1996. The Brookhart et al patent application does not teach the complexes of the present invention.
The recent paper (Chem. Comm (1998) p. 849) by Gibson and coworkers at Imperial College UK (and BP) teach complexes having a novel structure that is dissimilar to the complexes of the present invention. It is postulated that the complexes of Gibson et al. will have utility in the polymerization of certain monomers such as alpha olefins.
There has been a great deal of work recently by both Exxon in the field of metallocene chemistry and by the Dow Chemical Company in single site constrained geometry complexes. As far as applicant has been able to determine none of the chemistry proposed by either Exxon or Dow contain a carbene structure or a constrained alkyl carbon bonded to a transition metal. There are several patents relating to amidinato complexes of transition metals which are suitable for the polymerization of various olefins. U.S. Pat. No. 5,502,128 issued Mar. 26, 1996, assigned to University of Massachusetts, teaches such complexes may be used to polymerize vinyl aromatic monomers; and U.S. Pat. No. 5,707,913 issued Jan. 13, 1998, assigned to BASF, teaches such compounds may be used to polymerize olefins. Neither of these patents disclose complexes of the structure of the present invention.
U.S. Pat. No. 5,557,023 issued September 1996 teaches the use of some complexes of transition metals to oligomerize lower alpha olefins such as ethylene to higher olefins such as hexene and the like. The complexes of the patent do not contain a carbene structure or substituted carbon bonded to the transition metal.
Copending U.S. patent application Ser. No. 09/375,943 filed Aug. 17, 1999 in the name of R. G. Cavell et al. discloses the complexes useful in the catalyst of the present invention.
U.S. Pat. No. 6,060,568 issued May 9, 2000 in the name of the Applicant discloses complexes similar to those of the present invention except that the complexes contain only one R7 and one R8 substituent. The present invention provides for more than one R7 or R8 substituents. The sum of the subscripts a and b is a whole number greater than 2 and up to the sum of the valence and co-ordination number of the metal (i.e. both the electrovalence and coordinate valence).
Applicant has been unable to identify any prior art disclosing the catalyst of the present invention for the polymerization of olefins.
The present invention provides a process for the polymerization of one or more C2-12 alpha olefins in the presence of a complex selected from the group consisting of a complex of formula I: 
wherein M is a metal atom; R1, R2, R3 and R4 are independently selected from the group consisting of a saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radical which is unsubstituted or substituted by one or more substituents selected from the group consisting of a halogen atom and a C1-6, most preferably a C1-4 alkyl radical; R7 and R8 are independently selected from the group consisting of a hydrogen atom, a halogen atom, an amide of the formula xe2x80x94NR1R2, an imide of the formula xe2x95x90NR1, an alkoxide or aryl oxide group of the formula xe2x80x94OR1, a siloxy group of the formula xe2x80x94OSi(R1)3 wherein R1 and R2 are defined above, and a saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radical which is unsubstituted or substituted by a halogen atom or a C1-6 alkyl radical and a Lewis base (neutral coordinating ligands) which may contain a donor heteroatom including but not limited to ethers, tertiary amines, tertiary phosphines and cyclic amines; a and b are integers and a+b is an integer greater than 2 up to the sum of the valence and co-ordination number of M; and each R5 is independently selected from the group consisting of radicals selected from the group consisting of saturated and unsaturated straight chained, branched and cyclic hydrocarbyl radicals, preferably C1-15 saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals, most preferably C1-8 straight or branched alkyl radicals, C6-12 cyclic aliphatic or aromatic radicals, radicals of the formula Si(R6)3 wherein each R6 is independently selected from the group consisting of saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals, preferably C1-10 saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals and radicals of the formula III: 
wherein R9, R10, R11 and R12 are independently selected from the group consisting of a hydrogen atom, a fluorine atom, a NO2 radical, a C1-6 alkyl radical and a C8-12 aryl radical; E is an endocyclic nitrogen atom or a Cxe2x80x94CN group; and R14 is selected from the group consisting of a hydrogen atom, a sulfur atom, an oxygen atom, an amido radical which is unsubstituted or may be substituted by C1-20 alkyl radical, preferably a C1-6 alkyl radical or a radical of the formula xe2x80x94Si(R6)3 wherein R6 is as defined above, a C1-20 hydrocarbyl radical, a C6-12 aromatic radical and a radical of the formula III as defined above, each of which may contain one or more functional groups including a heteroatom acting as a Lewis base; and optionally R14 taken together with the metal may form a ring;
and an activator at a temperature from 20 to 250xc2x0 C. and at a pressure from 15 to 15,000 psi.
The present invention also provides a complex of formula I: 
wherein M, R1, R2, R3, R4, R5, R7, R8, R14, a and b are as defined above.
The term xe2x80x9cscavengerxe2x80x9d as used in this specification is meant to include those compounds effective for removing polar impurities from the reaction solvent. Such impurities can be inadvertently introduced with any of the polymerization reaction components, particularly with solvent, monomer and catalyst feed; and can adversely affect catalyst activity and stability. It can result in decreasing or even elimination of catalytic activity, particularly when an activator capable of ionizing the catalyst is also present.
In the catalyst of the present invention, the metal may be any transition metal. It may be an early transition metal such as Y, Ti, Zr, Hf, V or Cr or it may be a later transition metal such as Fe, Co, Ni, Pd or Pt or a post transition metal (Zn) or a lanthanide group, preferably Sm. Preferably the transition metal will be selected from group 3 through 10 (formerly group IIIB through VIII) of the Periodic Table.
In accordance with the present invention R1, R2, R3 and R4 may be independently selected from the group consisting of a saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radical which is unsubstituted or substituted by one or more substituents selected from the group consisting of a halogen atom and a C1-6, most preferably a C1-4 alkyl radical. Preferably, the hydrocarbyl radicals may be selected from the group consisting of a C1-10, preferably C1-8, most preferably C1-6 straight chained, branched or cyclic alkyl radicals which radicals may be unsubstituted or further substituted, preferably by not more than three substituents selected from the group consisting of C1-4 alkyl radicals or a halogen atom, preferably either F or Cl. Additionally, substituents R1, R2, R3 and R4 may be independently selected from the group consisting of C5-14 aromatic radicals which radicals are unsubstituted or substituted by up to nxe2x88x921, wherein n is the number of carbon atoms in the aromatic radical, substituents selected from the group consisting of a halogen atom, preferably F or Cl, a C1-6, most preferably a C1-4 alkyl radical or an amido radical which is unsubstituted or substituted by up to two C1-6, preferably C1-4 alkyl radicals.
The substituents R1, R2, R3 and R4 may be selected from the group consisting of a fluorine atom, a chlorine atom, a methyl radical, an ethyl radical, a propyl radical, a butyl radical, a tertiary butyl radical and a phenyl radical.
In some embodiments of the present invention R1 and R2 may be the same. In a further embodiment R3 and R4 may be the same. In a further embodiment of the present invention all of R1, R2, R3 and R4 may be the same.
In the present invention R7 and R8 may be independently selected from the group consisting of a halogen atom preferably a chlorine or fluorine atom, an amide xe2x80x94NR1R2, an imide of the formula xe2x95x90NR1; an alkoxide or aryl oxide group, xe2x80x94OR1; and an xe2x80x94OSi(R1)3 group wherein R1 and R2 are defined above; and a saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radical which are unsubstituted or substituted by a halogen atom or a C1-6 alkyl radical or a Lewis base (neutral coordinating ligands) which may contain a donor heteroatom including but not limited to ethers preferably C1-6 alkyl ethers or C4-8 cyclic ethers; tertiary amines preferably C1-6 tertiary amines; tertiary phosphines preferably tertiary C1-10 phosphines and cyclic amines preferably C4-8 cyclic amines (nitrogen containing compounds). The hydrocarbyl radical may be a straight chained or branched C1-10 alkyl radical which may be unsubstituted or substituted by a F or Cl atom or up to three C1-6, preferably C1-4 alkyl radicals. The hydrocarbyl radical may be selected from the group consisting of C5-14 aromatic radicals which radicals are unsubstituted or substituted by up to nxe2x88x921, wherein n is the number of carbon atoms in the aromatic radical, substituents selected from the group consisting of a halogen atom, preferably F or Cl, a C1-6, most preferably a C1-4 alkyl radical or an amido radical which is unsubstituted or substituted by up to two C1-6, preferably C1-4 alkyl radicals.
Both a and b are integers and the sum of a+b is an integer greater than 2 and up to the sum of the valence and co-ordination number of M. Typically the sum of a and b may be from 3 to 6 and a and b may be in the range of 2 or 3.
In accordance with the present invention each R5 is independently selected from the group consisting of radicals of a saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radical, preferably C1-15 saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals, most preferably a C1-8 straight or branched alkyl radical and a C6-12 cyclic aliphatic or aromatic radical; radicals of the formula Si(R6)3 wherein each R6 is independently selected from the group consisting of saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals, preferably C1-10 saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals of the formula III: 
wherein R9, R10, R11 and R12 are independently selected from the group consisting of a hydrogen atom, a fluorine atom, a NO2 radical, a C1-6 alkyl radical and a C8-12 aryl radical; and E is an endocyclic nitrogen atom or a Cxe2x80x94CN group.
Each R5 radical may be selected from the group consisting of radicals of the formula Si(R6)3 wherein each R6 is independently selected from the group consisting of saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals, preferably C1-10 saturated or unsaturated straight chained, branched or cyclic hydrocarbyl radicals. Most preferably R6 is selected from C1-8, preferably C1-6, most preferably C1-4 alkyl radicals. Suitable alkyl radicals include methyl, ethyl, propyl and butyl and adamantyl radicals. In a preferred embodiment of this aspect of the invention each R6 radical is the same.
R5 may also be a 4-cyanotetrafluorophenyl radical.
The catalyst of the present invention wherein the R7 and R8 are halogens and may be alkylated, aminated or alkoxylated by reacting with suitable alkylating agents such as LiR or RMgX, aminating agents such as MNR2 or an alkoxylating agent which is an alkali alkoxide (e.g. M2OR where M2 is selected from the group consisting of alkali metals, preferably lithium). In the alkylating, aminating or alkoxylating agent, the alkyl or alkoxide radical is as defined in R7 and R8 above.
Some hydrocarbon solvents include C5-12 hydrocarbons which may be unsubstituted or substituted by C1-4 alkyl group, such as pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane and hydrogenated naphtha. An additional solvent is Isopar E (C8-10 aliphatic solvent, Exxon Chemical Co.). The solvent may be aromatic such as benzene, toluene or xylene. The solvent may also be a simple or branched ether in which the alkyl radicals may contain from 1 to 10 carbon atoms or a polyether thereof such as diethyl ether and diglyme. The product is recovered using conventional procedures illustrated in the examples. The reaction may be carried out from room temperature (20xc2x0 C.) to about 150xc2x0 C.
In the compounds of formula I, M, R1, R2, R3, R4, R5, R7, R8, a and b are as defined above and R14 is selected from the group consisting of a hydrogen atom, a sulfur atom, an oxygen atom, an amido radical unsubstituted or may be substituted by a C1-20 alkyl radical preferably a C1-6 alkyl radical or a radical of the formula xe2x80x94Si(R6)3 wherein R6 is as defined above, a C1-20 hydrocarbyl radical, a C6-12 aromatic radical and a radical of the formula III as defined above, each of which may contain one or more functional groups including a heteroatom acting as a Lewis base such as:
(i) an amido group which may be unsubstituted or substituted by up to two substituents selected from the group consisting of a C1-20 alkyl radical preferably a C1-6 alkyl radical; a radical of the formula xe2x80x94Si(R6)3 wherein R6 is as defined above; a phosphine group which may be unsubstituted or further substituted by a substituent selected from the group consisting of a hydrogen atom, a halogen atom preferably fluorine or chlorine, a C1-6 alkyl or alkoxide radical, and an amide radical which is unsubstituted or substituted by up to two C1-6 alkyl radicals;
(ii) an imido group which is unsubstituted or may be substituted by C1-20 alkyl or C6-12 aromatic radical, preferably a C1-6 alkyl radical; a radical of the formula xe2x80x94Si(R6)3 wherein R6 is as defined above; an amido as defined above; a phosphine group which may be unsubstituted or substituted by a substituent selected from the group consisting of a halogen atom preferably fluorine or chlorine, a C1-6 alkyl or alkoxide radical, and an amide radical which is unsubstituted or substituted by up to two C1-6 alkyl radicals;
(iii) a phosphine group which may be unsubstituted or substituted by a substituent selected from the group consisting of a hydrogen atom, a halogen atom preferably fluorine or chlorine, a C1-6 alkyl or alkoxide radical, and an amide radical which is unsubstituted or substituted by up to two C1-6 alkyl radicals; and
(iv) a carbonyl or carboxyl group.
When R14 is a sulfur atom, an oxygen atom, an amido radical unsubstituted or may be substituted by C1-20 alkyl radical R14 together with M will form a ring.
R14 may be a straight, branched alkyl group which may or may not form a ring with M.
However, if R14 contains one or more functional groups as defined above, it may also form a ring with the metal and the functional groups may be exocyclic (pendant to the ring) or endocyclic (forming part of the ring).
In some cases where R14 is short or the heteroatom on R14 is close to the carbon behind the metal, the ring may be constrained.
The compounds of the formula I, as defined above, may be prepared by the reaction of a compound of formula II: 
wherein R1, R2, R3, R4, R5, R7, R8, a, b and M are as defined above with
(i) molecules of the type AB wherein A is selected from the group consisting of a hydrogen atom, a C1-20 alkyl group, a C6-12 aryl group, an amino group (as substituted as defined in R14), a C1-20 alkoxy group, a C1-20 alkylthio group, a C6-12 aryloxy group, a C6-12 arylthio group, and a radical of the formula III as defined above; and B is selected from the group consisting of a hydrogen atom provided that A is not a hydrocarbyl radical or a hydrogen atom and halogen atom;
(ii) compounds of the formula F=C=G wherein F and G are independently selected from the group consisting of an O or S atom preferably O; and radicals of the formula xe2x95x90Nxe2x80x94R15, wherein R15 is a C1-20 hydrocarbyl radical, a C6-12 aromatic radical, and a radical of the formula xe2x80x94Si(R6)3 wherein R6 is as defined above; xe2x95x90Pxe2x80x94(R16)d wherein d is 1 or 3; and R16 is selected from the group consisting of a hydrogen atom, a halogen atom, a C1-20 hydrocarbyl radical, a C1-20 alkoxide radical, a C6-12 aromatic radical, a C6-12 aryloxide radical, and radicals of the formula xe2x80x94Si(R6)3 or xe2x80x94Oxe2x80x94Si(R6)3 wherein R6 is as defined above.
The preparation of compounds of formula II is disclosed in U.S. Pat. No. 6,060,568 issued May 9, 2000 assigned to The Governors of the University of Alberta (the text of which is incorporated herein by reference).
The reaction of the compounds of formula II with a molecule of the type AB, a compound of the formula F=C=G may be carried out in a hydrocarbyl solvent which may be aliphatic or aromatic (such as toluene or benzene or similar solvents) at temperatures from room temperature (e.g. 20xc2x0 C.) up to about 120xc2x0 C. for a period of time from a few minutes (e.g. about 5 minutes) to several days, typically from 1 to 12 hours. The compound of formula I may be recovered by crystallization.
Compounds which contain an unsaturation include for example CO2, Oxe2x95x90Cxe2x95x90N-adamantyl, Oxe2x95x90Cxe2x95x90N(p-tolyl) and Oxe2x95x90C=NCy where Cy is cyclohexyl.
The catalyst of the present invention wherein R7 and R8 are not alkyl may be alkylated (either partially or fully). Some alkylating agents are Grignard agents of the formula RMgX and organolithium reagents of the formula LiR wherein R is a C1-10 alkyl radical and X is a halogen and alkyl aluminum reagents. Alkyl aluminum reagents include trialkyl aluminum and alkyl aluminum halides (i.e. (R)xAlX3-x wherein R is a C1-10 alkyl radical, X is a halogen, x is 1 or 2 and MAO as described below).
The polymerization may be conducted at temperatures from about 20 to about 250xc2x0 C. Depending on the product being made, this temperature may be relatively low such as from 20 to about 120xc2x0 C. (preferably less than 120xc2x0 C., i.e. 119xc2x0 C. and below). The pressure of the reaction may be as high as about 15,000 psig for the older high pressure processes or may range from about 15 to 4,500 psig. The temperatures for solution processes tend to be higher, typically from 120 to 250xc2x0 C.
Solution polymerization processes are fairly well known in the art. These processes are conducted in the presence of an inert hydrocarbon solvent typically a C5-12 hydrocarbon which may be unsubstituted or substituted by C1-4 alkyl group such as pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane or hydrogenated naphtha. An additional solvent is Isopar E (C8-12 aliphatic solvent, Exxon Chemical Co.).
Suitable olefin monomers may be ethylene and C3-20 mono- and di-olefins. Preferred monomers include ethylene and C3-12 alpha olefins which are unsubstituted or substituted by up to two C1-6 alkyl radicals. Illustrative non-limiting examples of such alpha olefins are one or more of propylene, 1-butene, 1-pentene, 1-hexene, 1-octene and 1-decene.
The polyethylene polymers which may be prepared in accordance with the present invention typically comprise not less than 60, preferably not less than 70, most preferably not less than 80 weight % of ethylene and the balance of one or more C4-10 alpha olefins, preferably selected from the group consisting of 1-butene, 1-hexene and 1-octene.
The complexes of the present invention may require the use of a support. An exemplary list of support materials include metal oxides (such as silica, alumina, silica-alumina, titania and zirconia), metal chlorides (such as magnesium chloride), talc, polymers (including polyolefins), ion exchangeable layer materials (or compounds), partially pre-polymerized mixtures of a group 4 metal complex, activators and polymers, spray dried mixtures of the group 4 metal complex, and activators and fine xe2x80x9cinertxe2x80x9d particles (as disclosed, for example, in European Patent Application 668,295 (to Union Carbide)).
The preferred support material is silica. In a particularly preferred embodiment, the silica has been treated with an alumoxane (especially methylalumoxane or xe2x80x9cMAOxe2x80x9d) prior to the deposition of the group 4 metal complex. The procedure for preparing xe2x80x9csupported MAOxe2x80x9d which is described in U.S. Pat. No. 5,534,474 (to Witco) is preferred for reasons of economy. It will be recognized by those skilled in the art that silica may be characterized by such parameters as particle size, pore volume and residual silanol concentration. The pore size and silanol concentration may be altered by heat treatment or calcining. The residual silanol groups provide a potential reaction site between the alumoxane and the silica (and, indeed, some off gassing is observed when alumoxane is reacted with silica having residual silanol groups). This reaction may help to xe2x80x9canchorxe2x80x9d the alumoxane to the silica (which, in turn, may help to reduce reactor fouling).
The preferred particle size, preferred pore volume and preferred residual silanol concentration may be influenced by reactor conditions. Typical silicas are dry powders having a particle size of from 1 to 200 microns (with an average particle size of from 30 to 100 being especially suitable); pore size of from 50 to 500 Angstroms; and pore volumes of from 0.5 to 5.0 cubic centimeters per gram. As a general guideline, the use of commercially available silicas, such as those sold by W. R. Grace under the trademarks Davison 948 or Davison 955, are suitable.
The activator may be selected from the group consisting of:
(i) an aluminoxane; and
(ii) an activator capable of ionizing the catalyst (which may be used in combination with an alkylating activator).
The aluminoxane activator may be of the formula (R20)2AlO(R20AlO)mAl(R20)2 wherein each R20 is independently selected from the group consisting of C1-20 hydrocarbyl radicals, m is from 0 to 50, and preferably R20 is a C1-4 alkyl radical and m is from 5 to 30. The aluminoxane activator may be used prior to the reaction but preferably in situ alkylation is typical (e.g. alkyl groups replacing leaving ligands, hydrogen or halide groups).
Activation with aluminoxane generally requires a molar ratio of aluminum in the activator to the catalyst from 20:1 to 1000:1. MAO may be the higher end of the above noted range.
The activator of the present invention may be a combination of an alkylating activator which also serves as a scavenger other than aluminoxane in combination with an activator capable of ionizing the catalyst.
The alkylating activator (which may also serve as a scavenger) may be selected from the group consisting of: (R)pMgX2-p wherein X is a halide, each R is independently selected from the group consisting of C1-10 alkyl radicals, preferably C1-8 alkyl radicals and p is 1 or 2; RLi wherein R is as defined above; (R)qZnX2-q wherein R is as defined above, X is halogen and q is 1 or 2; (R)sAlX3-s wherein R is as defined above, X is halogen and s is an integer from 1 to 3. Preferably, in the above compounds R is a C1-4 alkyl radical and X is chlorine. Commercially available compounds include triethyl aluminum (TEAL), diethyl aluminum chloride (DEAC), dibutyl magnesium ((Bu)2Mg) and butyl ethyl magnesium (BuEtMg or BuMgEt).
The activator capable of ionizing the catalyst may be selected from the group consisting of:
(i) compounds of the formula [R15]+[B(R18)4]xe2x88x92 wherein B is a boron atom, R15 is a cyclic C5-7 aromatic cation or a triphenyl methyl cation and each R18 is independently selected from the group consisting of phenyl radicals which are unsubstituted or substituted with from 3 to 5 substituents selected from the group consisting of a fluorine atom, a C1-4 alkyl or alkoxy radical which is unsubstituted or substituted by a fluorine atom, and a silyl radical of the formula xe2x80x94Sixe2x80x94(R19)3 wherein each R19 is independently selected from the group consisting of a hydrogen atom and a C1-4 alkyl radical; and
(ii) compounds of the formula [(R16)tZH]+[B(R18)4]xe2x88x92 wherein B is a boron atom; H is a hydrogen atom; Z is a nitrogen atom or phosphorus atom; t is 2 or 3; and R16 is selected from the group consisting of C1-8 alkyl radicals, a phenyl radical which is unsubstituted or substituted by up to three C1-4 alkyl radicals, or one R16 taken together with the nitrogen atom to form an anilinium radical and R18 is as defined above; and
(iii) compounds (activators) of the formula B(R18)3 wherein R18 is as defined above.
In the above compounds, preferably R18 is a pentafluorophenyl radical, R15 is a triphenylmethyl cation, Z is a nitrogen atom and R16 is a C1-4 alkyl radical or R16 taken together with the nitrogen atom to form an anilinium radical which is substituted by two C1-4 alkyl radicals.
The activator capable of ionizing the catalyst abstracts one or more of R7 or R8 so as to ionize the catalyst center into a cation, but not to covalently bond with the catalyst; and to provide sufficient distance between the ionized catalyst and the ionizing activator to permit a polymerizable olefin to enter the resulting active site.
Examples of compounds capable of ionizing the catalyst include the following compounds:
triethylammonium tetra(phenyl)boron,
tripropylammonium tetra(phenyl)boron,
tri(n-butyl)ammonium tetra(phenyl)boron,
trimethylammonium tetra(p-tolyl)boron,
trimethylammonium tetra(o-tolyl)boron,
tributylammonium tetra(pentafluorophenyl)boron,
tributylammonium tetra(pentafluorophenyl)boron,
tri(n-butyl)ammonium tetra(o-tolyl)boron,
N,N-dimethylanilinium tetra(phenyl)boron,
N,N-diethylanilinium tetra(phenyl)boron,
N,N-diethylanilinium tri(phenyl)n-butylboron,
N,N-2,4,6-pentamethylanilinium tetra(phenyl)boron,
di-(isopropyl)ammonium tetra(pentafluorophenyl)boron,
dicyclohexylammonium tetra(phenyl)boron,
triphenylphosphonium tetra(phenyl)boron,
tri(methylphenyl)phosphonium tetra(phenyl)boron,
tri(dimethylphenyl)phosphonium tetra(phenyl)boron,
tropillium tetrakispentafluorophenyl borate,
triphenylmethylium tetrakispentafluorophenyl borate,
benzene (diazonium) tetrakispentafluorophenyl borate,
tropillium phenyltrispentafluorophenyl borate,
triphenylmethylium phenyltrispentafluorophenyl borate,
benzene (diazonium) phenyltrispentafluorophenyl borate,
tropillium tetrakis (2,3,5,6-tetrafluorophenyl) borate,
triphenylmethylium tetrakis (2,3,5,6-tetrafluorophenyl) borate,
benzene (diazonium) tetrakis (3,4,5-trifluorophenyl) borate,
tropillium tetrakis (3,4,5-trifluorophenyl) borate,
benzene (diazonium) tetrakis (3,4,5-trifluorophenyl) borate,
tropillinum tetrakis (1,2,2-trifluoroethenyl) borate,
triphenylmethylium tetrakis (1,2,2-trifluoroethenyl) borate,
benzene (diazonium) tetrakis (1,2,2-trifluoroethenyl) borate,
tropillium tetrakis (2,3,4,5-tetrafluorophenyl) borate,
triphenylmethylium tetrakis (2,3,4,5-tetrafluorophenyl) borate, and
benzene (diazonium) tetrakis (2,3,4,5-tetrafluorophenyl) borate.
Readily commercially available activators which are capable of ionizing the catalyst include:
N,N-dimethylaniliniumtetrakispentafluorophenyl borate,
triphenylmethylium tetrakispentafluorophenyl borate, and
trispentafluorophenyl boron.
If the catalyst is activated with a combination of an aluminum alkyl compound (generally other than aluminoxane), and a compound capable of ionizing the catalyst; the molar ratios of catalyst:metal in the alkylating agent (e.g. Al):metalloid (e.g. boron or phosphorus) in the activator capable of ionizing the catalyst (e.g. boron) may range from 1:1:1 to 1:100:5. Preferably, the alkylating activator is premixed/reacted with the catalyst and the resulting alkylated species is then reacted with the activator capable of ionizing the catalyst.
In a solution polymerization, the monomers are dissolved/dispersed in the solvent either prior to being fed to the reactor or for gaseous monomers, the monomer may be fed to the reactor so that it will dissolve in the reaction mixture. Prior to mixing, the solvent and monomers are generally purified to remove polar moieties. The polar moieties or catalyst poisons include water, oxygen, metal impurities, etc. Preferably steps are taken before provision of such into the reaction vessel, for example by chemical treatment or careful separation techniques after or during the synthesis or preparation of the various components. The feedstock purification prior to introduction into the reaction solvent follows standard practices in the art (e.g. molecular sieves, alumina beds and oxygen removal catalysts) are used for the purification of ethylene, alpha olefin and optional diene. The solvent itself as well (e.g. cyclohexane and toluene) is similarly treated. In some instances, out of an abundance of caution, excess scavenging activators may be used in the polymerization process.
The feedstock may be heated prior to feeding into the reactor. However, in many instances it is desired to remove heat from the reactor so the feedstock may be at ambient temperature to help cool the reactor.
Generally, the components may be premixed in the solvent for the reaction or fed as separate streams to the reactor. In some instances, premixing is desirable to provide a reaction time for the catalyst components prior to entering the reaction. Such an xe2x80x9cin line mixingxe2x80x9d technique is described in a number of patents in the name of DuPont Canada Inc. For example, it is described in U.S. Pat. No. 5,589,555 issued Dec. 31, 1996.
The reactor may comprise a tube or serpentine reactor used in the xe2x80x9chigh pressurexe2x80x9d polymerizations or it may comprise one or more reactors or autoclaves. It is well known that the use in series of two such reactors each of which may be operated so as to achieve different polymer molecular weight characteristics. The residence time in the reactor system will depend on the design and the capacity of the reactor. Generally, the reactors should be operated under conditions to achieve a thorough mixing of the reactants. On leaving the reactor system, the solvent is removed and the resulting polymer is finished in a conventional manner.
The present invention will be illustrated by the following non-limiting examples in which, unless otherwise specified, part means parts by weight (e.g. grams) and percent means weight percent.
Synthesis of Ligands and Metal Carbene Complexes
General Experimental Conditions for Catalyst Synthesis
All experimental manipulations were performed under rigorously anaerobic conditions using Schlenk techniques or an argon-filled glovebox with an efficient recirculator. Solvents were dried and distilled under argon prior to use. Hexane and toluene were distilled from Naxe2x80x94K and Na respectively. NMR solvents benzene-d6 and toluene-d8 were freshly vacuum transferred from Naxe2x80x94K. Commercial (Aldrich) supplies of bis(diphenylphosphino)methane (dppm), Me3SiN3, ZrCl4 and HfCl4 were used as obtained. NMR spectra were recorded using Bruker(copyright) WH-200, 300 and 400 spectrometers with reference to the deuterium signal of the solvent employed. The 1H NMR chemical shifts are reported in ppm from external Me4Si and the 31P NMR spectra are reported in ppm from external 85% H3PO4. Positive values reflect shifts downfield. Infrared spectra were recorded on a Nicolet(copyright) 7199 infrared spectrometer.
Preparation of Ligands
Preparation of CH2[Cy2Pxe2x95x90NSiMe3]2 
To a solution of dcpm, {Cy2P}2CH2, {literature preparation: Fryzuk, M. D.; McConville, D. H.; Rettig, S. J.; J. Organomet. Chem. 1993, 445, 245-256.} (3.97 g, 9.72 mmol) in 60 mL of toluene was added trimethylsilyl azide (6 mL, 45.79 mmol) with stirring. The solution was heated to reflux at 110xc2x0 C. for 48 hours. Solvent was evaporated under vacuum to obtain microcrystalline solid which was washed twice with hexane and dried (Yield: 4.85 g, 85.6%). IR (Nujol mull): 2666 w, 2653 w, 1449 s, 1376 m, 1348 m, 1302 s, 1264 s, 1244 s, 1233 s, 1209 m, 1173 m, 1154 m, 1119 w, 1078 w, 1045 w, 1028 w, 1004 m, 913 w, 896 m, 852 s, 827 s, 787 s, 776 s, 751 s, 675 m, 663 m, 633 m, 571 w, 526 m. 1H NMR (C6D6): xcex4 1.95 (b.t, 4 H, CH-Cy methine), 1.7 (m, CH2-Cy methylene), 1.62 (d, 2JPH=12.2 Hz, 2 H, PCH2P methylene), 1.40-1.05 (m, CH2-Cy methylene), 0.38 (s, 18 H, CH3Si methyl). 13{1H} NMR (C6D6): xcex4 39.5 (m, 4 C, CH-Cy, methine), 27.1 (s, 4 C, para Cy), 27.0 (s, 8 C, ortho Cy), 26.8 (s, 4 C, meta Cy), 26.5 (s, 4 C, meta Cy), 21.6 (t, 1JPC=61.6 Hz, 1 C, P CH2P methylene), 5.3 (s, 6 C, CH3Si). 13C {1H, 31P} (C6D6): xcex4 39.5 (s, 4 C, CH-Cy, methine), 27.1 (s, 4 C, para Cy), 27.0 (s, 8 C, ortho Cy), 26.8 (s, 4 C, meta Cy), 26.5 (s, 4 C, meta Cy), 21.6 (s, 1 C, P CH2P methylene), 5.3 (s, 6 C, CH3Si). 31P{1H} NMR (C6D6): xcex4 14.6 (2 P). Analysis calculated for C31H64N2P2Si2: C, 63.87; H, 11.06; N, 4.81. Found: C, 63.55; H, 11.22; N, 4.63.
Preparation of CH2 [Ph2Pxe2x95x90NSiMe3]2 
As described in the literature {Appel, R.; Ruppert, I. Z.; Anorg. Allg. Chem. 1974, 406, 131-144.}.
Preparation of CH2(Ph2P=and)2 
Adamantyl azide (1.66 g, 9.37 mmol) was added to a solution of bis(diphenylphosphino)methane (dppm) (1.80 g, 4.68 mmol) in 60 mL of toluene. The mixture was heated to reflux at 110xc2x0 C. for 2 days. The solution was then cooled to room temperature, concentrated to about 20 mL and maintained at xe2x88x9215xc2x0 C. to yield, after about 12 hours, a microcrystalline solid which was filtered and dried (Yield: 2.56 g, 80%). 1H NMR (toluene-d8): xcex4 7.87 (b.s, 8 H, ortho-Ph), 7.05 (b.s, 12 H, meta and para-Ph), 3.48 (b.t, 2 H, CH2), 1.99 (b.s, 3 H, CH-Ad), 1.93 (b.s, 6 H, CH2-Ad), 1.59 (b.s, 6 H, CH2-Ad). 31P{1H} NMR (toluene-d8): xcex4-15.4 (s). Analysis calculated for C45H52N2P2: C, 79.15; H, 7.68; N, 4.10. Found: C, 78.58; H, 7.93; N, 4.03.
Preparation of Me3Sixe2x95x90NPPh2CH2Ph2Pxe2x95x90NC6-p-CN
To a solution of bis(diphenylphosphoranotrimethylsilylimino)methane (11.17 g, 20 mmol) in dichloromethane a solution of pentafluorobenzonitrile (4.05 g, 21 mmol) in dichloromethane (35 mL) was added at room temperature. Immediately the solution turned yellow and after stirring for 12 hours became orange. The solvent was completely removed in vacuo leaving the slightly orange colored crude product which was recrystallized from acetonitrile giving the pure ligand (yield 10.28 g, 78%; white cubic crystals; mp 198-200xc2x0 C.). Analysis calculated for C35H31F4N3P2Si: C, 63.77; H, 4.69; N, 6.36. Found: C, 63.01; H, 4.70; N, 6.46. MS (EI, m/z): 659 (M+). 1H NMR (CD2Cl2): phenyl rings xcex4 7.80 to 7.74 ppm, 7.57 to 7.29 ppm (m, 20H); PCH2 P methylene, xcex4 3.75 ppm (xe2x80x98txe2x80x99, 2H, 2JHP 13.39 Hz); Me3 Si methyl xcex4 xe2x88x920.29 ppm (s, 9H). 19F{1H} NMR (CDCl2): ortho xcex4-140.17 ppm (m, 2 F); meta xcex4-153.32 ppm (m, 2 F). 29Si{1H} NMR (CDCl2), xcex4-10.59 ppm (d, 2JSiP 20.49 Hz).
Preparation of {Li2C{Ph2Pxe2x95x90NSiMe3}2}
Colorless crystalline bis(diphenylphosphoranotrimethysilylimino)methane H2C{Ph2Pxe2x95x90NSiMe3}2 (1.0 g, 1.79 mmol) was dissolved in 20 mL of toluene. To this toluene solution, PhLi (0.30 g, 3.59 mmol) was added with stirring. The reaction mixture was stirred at room temperature for 3 days. Approximately 100 mg of colorless solid was removed by filtration. The clear solution was reduced to one-half volume and allowed to stand at room temperature for 48 hours whereupon colorless crystals deposited. (Yield: 0.62 g, 60.7%). IR (Nujol mull): 1434 m, 1244 s, 1190 s, 1174 m, 1101 s, 1067 s, 852 s, 832 s, 764 m, 747 m, 725 m, 709 m, 696 s, 675 w, 663 w, 646 s, 618 w, 606 w, 539 s, 512 m. 1H NMR (C6D6): xcex4 7.53-7.49 (m, phenyl), 7.04-6.93 (m, phenyl), 0.04 (s, CH3Si methyl). 13C{1H} NMR (C6D6): xcex4 139.0 (m, 4 C, ipso phenyl), 131.0 (t, 2JPC=4.5 Hz, 8 C, ortho phenyl), 129.0 (s, 4 C, para phenyl), 127.8 (s, 8 C, meta phenyl), 4.4 (s, 6 C, CH3Si). 31P {1H} NMR (C6D6): xcex4 13.7 (2 P). Analysis calculated for C31H38Li2N2P2Si2: C, 65.25; H, 6.71; N, 4.91. Found: C, 65.27; H, 6.69; N, 4.60.
Preparation of Metal Carbene and Related Derivatives
Preparation of [ZrCl2{C(Cy2xe2x95x90NSiMe3)2}] (Zr-3C)
[ZrCl2{N(SiMe3)2}2] (0.5 g, 1.04 mmol) {literature preparation: Andersen, R. A.; Inorg. Chem. 1979, 18, 1724-1725} was dissolved in 15 mL of toluene by stirring. Solid bisimine ligand, CH2(Cy2Pxe2x95x90NSiMe3)2 (0.604 g, 1.04 mmol) was added to the solution which was then heated to reflux at 130xc2x0 C. for five days. The pale yellow solution was concentrated to about 10 mL and left at room temperature for 24 hours whereupon pale yellow crystals formed which were isolated by filtration (0.42 g). The mother liquor was concentrated to 5 mL, hexane was added and the total mixture was cooled to xe2x88x9215xc2x0 C. for 24 hours which yielded a second crop of product (0.15 g). Yield: 0.57 g, 75.2%). IR (Nujol mull): 1447 s, 1403 w, 1377 m, 1356 w, 1321 s, 1258 s, 1246 s, 1200 w, 1192 m, 1176 m, 1167 w, 1111 m, 1049 b.s, 998 m, 915 w, 887 m, 837 s, 779 m, 769 s, 753 m, 746 s, 679 m, 651 s, 634 m, 609 s, 551 s, 509 w, 495 m, 484 w, 465 w. 1H NMR (C6D6): xcex4 2.1-1.1 (b.m, 40 H, CH2-Cy methylene), 1.76 (m, 4 H, CH-Cy methine) (as assigned from a 1H-13C HMQC expt.), 0.51 (s, 18 H, CH3Si methyl). 13C {1H} NMR (C6D6): xcex4 86.9 (t, 1JPC=156.0 Hz, 1 C, PCP carbene), 40.3 (m, 4 C, CH-Cy, methine), 26.8 (m, 8 C, ortho Cy), 26.6 (s, 4 C, para Cy), 26.3 (s, 4 C, meta Cy), 26.1 (s, 4 C, meta Cy), 3.4 (s, 6 C, CH3Si). 13C {1H, 31P} NMR (C6D6): xcex4 86.9 (s, 1 C, PCP carbene), 40.3 (s, 4 C, CH-Cy, methine), 26.9 (s, 4 C, ortho Cy), 26.8 (s, 4 C, ortho Cy), 26.6 (s, 4 C, para Cy), 26.3 (s, 4 C, meta Cy), 26.1 (s, 4 C, meta Cy), 3.4 (s, 6 C, CH3Si). 31P{1H} NMR (C6D6): xcex4 35.5 (2 P). Analysis calculated for C31H62Cl2N2P2Si2Zr: C, 50.11; H, 8.41; N, 3.77. Found: C, 49.97; H, 8.68; 3.63.
Preparation of [ZrMe2{C(Cy2xe2x95x90NSiMe3)2}] Zr-3C(Me2)
To a toluene solution (xcx9c20 mL) of Zr-3C (0.207 g, 0.278 mmol) at xe2x88x9278xc2x0 C. was added a 3M diethyl ether solution of MeMgBr (0.241 mL, 0.723 mmol). The reaction mixture was warmed to room temperature, stirred for 2 hours and pumped to dryness. The solid was extracted with heptane (3xc3x9715 mL) and the heptane extract was slowly evaporated to dryness. Colorless crystals of Zr-3C(Me2) were obtained (136 mg, plus xcx9c30 mg left in flask).
Preparation of [ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2}] (Zr-3D)
[ZrCl2{N(SiMe3)2}2] {literature preparation: Andersen, R. A.; Inorg. Chem. 1979, 18, 1724-1725.} (1.0 g, 2.07 mmol) was dissolved in 20 mL of toluene by stirring. The bisimine ligand, CH2(Ph2Pxe2x95x90NSiMe3)2, (1.16 g, 2.08 mmol) was added as a solid to the solution which was then heated to reflux at 130xc2x0 C. for 24 hours. The resultant pale yellow solution was concentrated to nearly 5 mL and mixed with 5 mL of hexane. Upon cooling overnight, a pale yellow crystalline solid was obtained which was isolated by filtration (Yield: 1.05 g, 70.5%). IR (Nujol mull): 1653 w, 1480 w, 1462 m, 1436 s, 1378 w, 1304 s, 1251 s, 1179 w, 1156 w, 1112 s, 1061 s, 1042 s, 1026 m, 999 w, 842 s, 785 m, 771 w, 753 w, 747 w, 737 w, 714 s, 695 s, 652 s, 631 m, 613 s, 571 m, 522 s. 1H NMR (C6D6): xcex4 7.6 (m, phenyl), 6.98 (m, phenyl), 6.92 (m, phenyl), 6.90 (m, phenyl), 0.25 (s, 18 H, CH3Si methyl). 13C {1H} NMR (C6D6): xcex4 134.2 (m, 4 C, ipso phenyl), 131.5 (t, 2JPC=6.0 Hz, 8 C, ortho phenyl), 131.2 (s, 4 C, para phenyl), 128.5 (t, 3JPC=6.2 Hz, 8 C, meta phenyl), 101.7 (t, 1JPC=146 Hz, 1 C, PCP carbene), 2.6 (s, 6 C, CH3Si). 13C {1H, 31P} NMR (C6D6): xcex4 134.2 (s, 4 C, ipso phenyl), 131.5 (s, 8 C, ortho phenyl), 131.2 (s, 4 C, para phenyl), 128.5 (s, 8 C, meta phenyl), 101.7 (s, 1 C, PCP carbene), 2.6 (s, 6 C, CH3Si). 31P{1H} NMR (C6D6): xcex4 15.7 (2 P). Analysis calculated for C31H38Cl2N2P2Si2Zr: C, 51.79; H, 5.33; N, 3.90. Found: C, 51.41; H, 5.78; N, 3.80.
Preparation of [ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2}] (Zr-3D) Method B
To a suspension of ZrCl4(THF)2 (0.13 g, 0.35 mmol) in diethyl ether (5 mL) the dilithium salt Li2C(Ph2Pxe2x95x90NSiMe3)2 (0.20 g, 0.35 mmol) was added with stirring at room temperature. The mixture was stirred at room temperature for 2 days. Diethyl ether was removed and the resultant solid product was extracted with 5 mL of toluene and filtered to remove LiCl. The toluene solution was then concentrated to half the initial volume and the solution cooled to xe2x88x9215xc2x0 C. for 2 days whereupon colorless crystals of {ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2} precipitated (Yield: 0.16 g, 63.5%). All spectroscopic and analytical data indicated that the product was identical with the compound identified as {ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2} as described above.
Preparation of HfCl2{C(Cy2Pxe2x95x90NSiMe3)2 
The complex, [HfCl2{N(SiMe3)2}2] (0.2 g, 0.35 mmol) was dissolved in 10 mL of toluene. Solid CH2(Cy2Pxe2x95x90NSiMe3)2 (0.204 g, 0.35 mmol) was added to this solution with stirring and the colorless solution was heated at 140xc2x0 C. for seven days. The resultant pale yellow solution was concentrated and cooled to xe2x88x9215xc2x0 C. for 24 hours to obtain colorless crystals which were isolated by filtration (Yield: 0.21 g, 72.1%). IR (Nujol mull): 1447 s, 1404 w, 1377 w, 1356 w, 1320 s, 1297 w, 1260 s, 1246 s, 1202 w, 1192 w, 1176 w, 1168 w, 1112 m, 1024 b.s, 915 w, 887 m, 836 b.s, 783 m, 771 s, 754 s, 747 s, 707 w, 679 m, 654 s, 635 m, 615 s, 552 s, 542 m, 495 m, 485 m, 464 w. 1H NMR (400.1 MHz, C6D6, 298 K): xcex4 2.1-1.1 (b.m, 40 H, methylene-Cy and 4 H, methine-Cy), 0.47 (s, 18 H, methyl-TMS). 13C {1H} NMR (100.6 MHz, C6D6, 298 K): xcex4 66.6 (t, 1JPC=158.0 Hz, 1 C, quaternary Cxe2x80x94PCP), 40.7 (m, 4 C, methine-Cy), 26.8 (m, 8 C, ortho methylene-Cy), 26.6 (s, 4 C, para methylene-Cy), 26.4 (s, 4 C, meta methylene-Cy), 26.3 (s, 4 C, meta methylene-Cy), 3.5 (s, 6 C, methyl-TMS). 31P{1H} NMR (161.9 MHz, C6D6, 298 K): xcex4 32.6 (2 P). Analysis calculated for C31H62Cl2HfN2P2Si2: C, 44.84; H, 7.53; N, 3.37. Found: C, 45.04; H, 7.98; N, 3.29.
Preparation of HfCl2{C(Ph2Pxe2x95x90NSiMe3)2 
In a similar fashion, [HfCl2{N(SiMe3)2}2] (0.104 g, 0.18 mmol) in toluene solution was treated with solid CH2(Ph2Pxe2x95x90NSiMe3)2 (0.102 g, 0.18 mmol) and heated at 140xc2x0 C. for 3 days. The solution was reduced to a small volume and layered with hexane. After 2 days at ambient temperature, colorless crystals were deposited which were isolated by filtration (Yield: 0.11 g, 74.8%). IR (Nujol mull): 1589 w, 1574 w, 1480 w, 1463 m, 1436 s, 1378 m, 1311 s, 1251 s, 1181 w, 1156 w, 1111 s, 1070 m, 1057 s, 1037 s, 999 m, 843 s, 787 s, 772 m, 754 m, 738 m, 716 s, 696 s, 654 s, 631 m, 622 s, 615 m, 576 m, 524 s. 1H NMR (400.1 MHz, C6D6, 298 K): xcex4 7.63 (m, phenyl), 6.97 (m, phenyl), 6.91 (m, phenyl), 0.22 (s, 18 H, CH3Si methyl). 13C {1H} NMR (100.6 MHz, C6D6, 298 K): xcex4 134.7 (m, 4 C, ipso phenyl), 131.5 (t, 2JPC=6.0 Hz, 8 C, ortho phenyl), 131.0 (s, 4 C, para phenyl), 128.5 (t, 3JPC=5.6 Hz, 8 C, meta phenyl), 84.6 (t, 1JPC=145.0 Hz, 1 C, quaternary Cxe2x80x94PCP), 2.6 (s, 6 C, methyl-TMS). 31P{1H} NMR (161.9 MHz, C6D6, 298 K): xcex4 12.2 (2 P). Analysis calculated for HfCl2{C(Ph2Pxe2x95x90NSiMe3)2}] 0.5 toluene, C34.5H42Cl2HfN2P2Si2: C, 48.62; H, 4.97; N, 3.29. Found: C, 48.24; H, 5.21; N, 3.34.
Preparation of [Zr{C(Ph2Pxe2x95x90NSiMe3)2}(CH2C6H5)2] (Zr-6D)
[Zr(CH2C6H5)4] (1.0 g, 2.19 mmol) {literature preparation: Zucchini, U.; Albizzati, E.; Giannini, U.; J. Organomet. Chem. 1971, 26, 357-372.} was added to 15 mL of toluene and stirred at room temperature. To the pale yellow brown suspension was added solid bisimine ligand, CH2(Ph2Pxe2x95x90NSiMe3)2 (1.226 g, 2.19 mmol) at room temperature. The reaction mixture was stirred at room temperature for 2 days during which time a pale brown microcrystalline solid precipitated. The product was isolated by filtration, washed with a few mL of hexane and dried (Yield: 1.34 g, 73.5%). IR (Nujol mull): 1900-1650 w, 1591 m, 1488 m, 1481 m, 1466 m, 1436 m, 1378 m, 1334 w, 1283 s, 1260 s, 1249 s, 1216 m, 1204 m, 1173 m, 1151 w, 1110 s, 1016 b.s, 971 m, 880 w, 834 b.s, 793 w, 776 s, 764 m, 743 s, 734 m, 720 s, 693 s, 656 s, 620 m, 614 m, 562 s. 1H NMR (C6D6): xcex4 7.34 (m, phenyl), 7.26 (m, phenyl), 7.24 (m, phenyl), 7.02 (m, phenyl), 6.93 (m, phenyl), 2.62 (s, 4H, CH2Ph methylene), 0.09 (s, 18 H, CH3Si methyl). 13C {1H} (C6D6): xcex4 147.7 (s, 2 C, ipso benzyl), 135.9 (m, 4 C, ipso phenyl), 131.6 (t, 2JPC=6.0 Hz, 8 C, ortho phenyl), 130.5 (s, 4 C, ortho benzyl), 128.9 (s, 4 C, meta benzyl), 128.2 (t, 3JPC=6.5 Hz, 8 C, meta phenyl), 126.8 (s, 4 C, para phenyl), 121.2 (s, 2 C, para benzyl), 84.7 (t, 1JPC=164 Hz, 1 C, PCP carbene), 68.8 (s, 2 C, CH2Ph methylene), 3.6 (s, 6 C, CH3Si). 13C {1H, 31P} NMR (C6D6): xcex4 147.7 (s, 2 C, ipso benzyl), 135.9 (s, 4 C, ipso phenyl), 131.6 (s, 8 C, ortho phenyl), 130.5 (s, 4 C, ortho benzyl), 128.9 (s, 4 C, meta benzyl), 128.2 (s, 8 C, meta phenyl), 126.8 (s, 4 C, para phenyl), 121.2 (s, 2 C, para benzyl), 84.7 (s, 1 C, PCP carbene), 68.8 (s, 2 C, CH2Ph methylene), 3.6 (s, 6 C, CH3Si). 31P{1H} NMR (C6D6): xcex4 12.4 (2 P). Analysis calculated for C45H52N2P2Si2Zr: C, 65.10; H, 6.31; N, 3.37. Found: C, 65.65; H, 6.03; N, 3.31.
Preparation of [{(Me3SiNxe2x95x90PCy2)2CH}Li(OEt2)]
Colorless crystalline bis(dicyclohexylphosphoranotrimethylsilylimino)methane H2C{Cy2Pxe2x95x90NSiMe3}2 (0.2 g, 0.34 mmol) was dissolved in 5 mL of toluene. To this solution MeLi was added (1.4 M solution in diethyl ether, 0.49 mL, 0.69 mmol) with stirring. The reaction mixture was stirred at room temperature for 3 days. Concentration of the mother solution to nearly half the original volume and leaving the flask at xe2x88x9215xc2x0 C. for 48 hours yielded colorless crystals. (Yield: 0.145 g, 63.8%). IR (Nujol mull): 1269 m, 1242 s, 1223 s, 1211 s, 1197 s, 1167 s, 1151 s, 1113 m, 1071 w, 1007 m, 987 s, 893 m, 875 m, 850 s, 822 s, 777 m, 752 s, 730 w, 666 m, 641 w, 601 m, 562 s. 1H NMR (C6D6): xcex4 3.39 (q, CH2, Et2O), 2.05-1.24 (m, cyclohexyl), 1.09 (t, CH3, Et2O), 0.03 (s, CH3Si), xe2x88x920.02 (s, CH, Pxe2x80x94CHxe2x80x94P). 13C {1H} NMR (C6D6): xcex4 65.2 (s, CH2, Et2O), 41.2 (d, 1JPC=63.0 Hz, ipso cyclohexyl), 27.5 (m, ortho and para cyclohexyl), 27.0 (s, meta cyclohexyl), 15.1 (s, CH3, Et2O), 5.3 (t, 1JPC=128.6 Hz, CH, P-CH-P) 5.08 (s, CH3Si). 31P{1H} NMR (C6D6): xcex4 36.7 (2 P)., Analysis calculated for C35H73LiN2OP2Si2: C, 63.43; H, 11.10; N, 4.23. Found: C, 63.19; H, 10.97 N, 4.30.
Preparation of [ZrCl2{HC(Ph2Pxe2x95x90NSiMe3)2}(Ad)]
The zirconium dichloride carbene complex, [ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2}] (0.120 g, 0.17 mmol) was dissolved in 5 mL of toluene. To this colorless solution was added solid adamantanol (0.025 g, 0.17 mmol). With stirring a pale yellow solution was obtained. After 30 minutes, the solution was concentrated to nearly half of the original volume and mixed with few mL of hexane. Upon cooling overnight, a micro-crystalline solid was deposited which was isolated by filtration (Yield: 0.096 g, 66.0%). 1H NMR (toluene-d8, 25xc2x0 C.): xcex4 7.95 (b, phenyl), 7.09 (b, phenyl), 6.83 (b, phenyl), 6.63 (b, phenyl), 2.28 (t, 2JPH=2.7 Hz, 1 H, methine Pxe2x80x94Cxe2x80x94P), 2.17 (b.s, 6H, methylene Ad), 2.02 (b.s, 3H, methine Ad), 1.53 (b.dd, 6H, methylene Ad), 0.53 (s, 18H, methyl CH3Si). 31P NMR (toluene-d8, 25xc2x0 C.): xcex4 20.1 (b.s, 2P).
Preparation of [ZrCl2{(C(O)(NAd))C(Ph2Pxe2x95x90NSiMe3)2}] (KB-103)
Solid adamantyl isocyanate (AdNCO) (0.049 g, 0.28 mmol) was added to a stirred, colorless solution of [ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2}] (0.2 g, 0.28 mmol) in 10 mL of toluene. A white precipitate formed immediately. The resultant suspension was heated at 120xc2x0 C. for few minutes to dissolve the precipitate. On cooling to room temperature, colorless crystals of the product precipitated which were separated by filtration (Yield: 0.185 g, 74.2%). 1H NMR (C6D6): xcex4 8.23 (b.q, phenyl), 7.42 (b.q, phenyl), 7.12 (m, phenyl (toluene)), 7.06 (m, phenyl (toluene)), 7.01 (m, phenyl (toluene)), 6.64 (b.t, phenyl), 6.52 (b.t, phenyl), 2.12 (b.s, 6H, CH2-Ad methylene), 2.10 (s, CH3 toluene), 1.88 (b.s, 3H, CH-Ad methine), 1.62 (b.d, 2JHH=12.0 Hz, 3H, CH2-Ad methylene), 1.42 (d, 2JHH=12.0 Hz, 3H, CH2-Ad methylene), 0.55 (s, 18 H, CH3Si methyl). 13C {1H} NMR (C6D6): xcex4 159.8 (t, 1C, 2JPC=6.9 Hz, quaternary Cxe2x95x90O), 137.9 (s, 2C, ipso phenyl (toluene)), 134.3 (t, 2JPC=5.5 Hz, 8 C, ortho phenyl), 132.7 (s, 4 C, para phenyl), 131.98 (t, 3JPC=5.4 Hz, 8 C, meta phenyl), 131.6 (s, 4 C, ortho phenyl (toluene)), 130.1 (m, 4C, ipso phenyl), 129.3 (s, 4C, meta phenyl (toluene)), 125.6 (s, 2 C, para phenyl (toluene)), 57.6 (s, 1C, Ad quaternary carbon), 39.5 (s, 3C, CH2-Ad methylene), 36.9 (s, 3C, CH2-Ad methylene), 30.1 (s, 3C, CH-Ad methine), 24.7 (t, 1JPC=98.0 Hz, 1 C, quaternary PCP carbon), 21.4 (s, CH3 (toluene)), 4.6 (s, 6 C, CH3Si). 31P{1H} NMR (C6D6): xcex4 24.6 (2 P).
Preparation of [HfCl2{(C(O)(NAd))C(Ph2Pxe2x95x90NSiMe3)2}]
Solid adamantyl isocyanate (0.044 g, 0.25 mmol) was added to a stirred colorless solution of [HfCl2{C(Ph2Pxe2x95x90NSiMe3)2}] (0.2 g, 0.25 mmol) in 10 mL of toluene. The reaction mixture was stirred at room temperature for an hour and left to stand at room temperature for two days. During that period colorless crystals formed which were subsequently isolated by filtration (0.17 g). The remaining mother liquor was concentrated to about 4 mL, layered with hexane and left to stand at xe2x88x9215xc2x0 C. In two days second fraction of colorless crystals were obtained which were separated by filtration (0.064 g). The total yield was 0.234 g, 0.20 mmol, 80.8%. IR (Nujol mull): 1634 s, 1590 w, 1457 s, 1438 s, 1377 m, 1308 w, 1266 m, 1255 s, 1234 s, 1186 w, 1115 s, 1054 s, 1008 s, 924 w, 841 s, 773 s, 749 s, 727 s, 711 s, 695 m, 675 w, 659 m, 647 w, 616 m, 529 s. 1H NMR (C6D6): xcex4 8.24 (b.q, phenyl), 7.43 (b.q, phenyl), 7.08 (m, phenyl (toluene)), 7.04 (m, phenyl (toluene)), 7.01 (m, phenyl (toluene)), 6.65 (b.t, phenyl), 6.52 (b.t, phenyl), 2.12 (b.s, 6H, CH2-Ad methylene), 2.10 (s, 6H, CH3 toluene), 1.90 (b.s, 3H, CH-Ad methine), 1.62 (b.d, 2JHH=11.7 Hz, 3H, CH2-Ad methylene), 1.43 (b.d, 2JHH=11.7 Hz, 3H, CH2-Ad methylene), 0.54 (s, 18 H, CH3Si methyl). 13C {1H} NMR (C6D6): xcex4 159.7 (t, 1C, 2JPC=6.4 Hz, quaternary Cxe2x95x90O), 137.8 (s, 2C, ipso phenyl (toluene)), 134.3 (t, 2JPC=5.5 Hz, 8 C, ortho phenyl), 132.6 (s, 4 C, para phenyl), 131.9 (t, 3JPC=5.2 Hz, 8 C, meta phenyl), 131.6 (s, 4 C, ortho phenyl (toluene)), 130.3 (m, 4C, ipso phenyl), 129.3 (s, 4C, meta phenyl (toluene)), 125.6 (s, 2 C, para phenyl (toluene)), 56.6 (s, 1C, Ad quaternary carbon), 39.6 (s, 3C, CH2-Ad methylene), 36.9 (s, 3C, CH2-Ad methylene), 30.2 (s, 3C, CH-Ad methine), 25.2 (t, 1JPC=97.1 Hz, 1 C, quaternary PCP carbon), 21.4 (s, 2 C, CH3 (toluene)), 4.7 (s, 6 C, CH3Si). 31P{1H} NMR (C6D6): xcex4 24.8 (2 P). Analysis calculated for C45.5H57Cl2HfN3OP2Si2: C, 53.08; H, 5.58; N, 4.08. Found: C, 53.58; H, 5.73; N, 3.94. (The crystal became opaque when it was taken out of solvent and slowly loses the lattice solvent molecules. The analysis was calculated for the formula [HfCl2{(C(O)(NAd))C(Ph2Pxe2x95x90NSiMe3)2}].0.5C6H5CH3).
Preparation of HfNp2{C(Ph2Pxe2x95x90NSiMe3)2}
Solid neo-pentyl lithium (0.037 g, 0.47 mmol) was added to a stirred toluene solution (10 mL) containing [HfCl2{C(Ph2Pxe2x95x90NSiMe3)2}].0.5 toluene (0.2 g, 0.24 mmol) at room temperature. After 24 hours the suspension was filtered and evaporated to dryness. The residual solid was dissolved in few mL of hexane. This solution was cooled at xe2x88x9215xc2x0 C. for 2 days. Colorless crystals obtained were collected by filtration. Yield: 0.12 g, 56%. 1H NMR (400.1 MHz, C6D6, 298 K): xcex4 7.67 (m, 8 H, o-Ph), 6.97 (m, 12 H, m-Ph and p-Ph), 1.41 (s, 18 H, CH3xe2x80x94Np), 1.19 (s, 4 H, CH2xe2x80x94Np), 0.22 (s, 18 H, CH3xe2x80x94SiMe3). 13C {1H} NMR (100.6 MHz, C6D6, 298 K): xcex4 137.2 (m, ipso-Ph), 131.8 (t, 2JPC=5 Hz, o-Ph), 130.4 (s, p-Ph), 127.9 (t, 3JPC=6 Hz, m-Ph), 98.5 (s, CH2xe2x80x94Np), 71.6 (t, 1JPC=160 Hz, quaternary Cxe2x80x94PCP), 36.7 (s, CH3xe2x80x94Np), 36.5 (s, quaternary Cxe2x80x94Np), 4.2 (s, CH3xe2x80x94SiMe3). 31P{1H} NMR (161.9 MHz, C6D6, 298 K): xcex4 10.3 (s). Analysis calculated for C41H60HfN2P2Si2: C, 56.12; H, 6.89; N, 3.19. Found: C, 55.72; H, 6.80; N, 3.12.
Preparation of Hf(AdCN)Cl2{C(Ph2Pxe2x95x90NSiMe3)2}
Solid adamantyl nitrile (0.038 g, 0.24 mmol) was added to a stirred toluene solution (10 mL) of [HfCl2{C(Ph2Pxe2x95x90NSiMe3)2}].0.5 toluene (0.2 g, 0.24 mmol) at room temperature. After one hour, the solution was concentrated to one-third of the original volume and left standing at room temperature for three days. Colorless crystals deposited which were collected by filtration. Yield: 0.18 g, 81%. IR (Nujol mull): 2276 m, 2252 w (vCN). 1H NMR (400.1 MHz, C6D6, 298 K): xcex4 7.69 (m, 8 H, o-Ph), 7.00 (m, 12 H, m-Ph and p-Ph), 1.62 (b.s, 6 H, CH2-Ad), 1.48 (b.s, 3 H, CH-Ad), 1.24 (b.d, 6 H, CH2-Ad), 0.26 (s, 18 H, CH3xe2x80x94SiMe3). 13C {1H} NMR (100.6 MHz, C6D6, 298 K): xcex4 135.5 (m, ipso-Ph), 131.6 (t, 2JPC=5 Hz, o-Ph), 130.9 (s, p-Ph), 128.3 (t, 3JPC=6 Hz, m-Ph), 125.4 (s, quaternary Cxe2x80x94CN), 83.4 (t, 1JPC=153 Hz, quaternary Cxe2x80x94PCP), 39.4 (s, CH2-Ad), 35.5 (s, CH2-Ad), 30.2 (s, quaternary C-Ad), 27.1 (s, CH-Ad), 2.8 (s, CH3xe2x80x94SiMe3). 31P{1H} NMR (161.9 MHz, C6D6, 298 K): xcex4 11.4 (s). Analysis calculated for C42H53Cl2HfN3P2Si2: C, 52.15; H, 5.52; N, 4.34. Found: C, 52.23; H, 5.12; N, 4.25.
Preparation of HfCl2(HN(p-tolyl)){HC(Ph2Pxe2x95x90NSiMe3)2}
Solid toluidine (0.019 g, 0.18 mmol) was added to a stirred toluene solution (10 mL) of [HfCl2{C(Ph2Pxe2x95x90NSiMe3)2}].0.5 toluene (0.15 g, 0.18 mmol) at room temperature. A white solid precipitated within one hour which was collected and dissolved in THF (5 mL). The resultant clear pale yellow solution was cooled at xe2x88x9215xc2x0 C. for 3 days whereupon crystals deposited which were collected by filtration. The room temperature NMR spectrum of the product in THF-d8 displayed broad peaks. However, at low temperature (xe2x88x9240xc2x0 C.) sharp signals were observed which were assignable to two geometrical isomers of the product complex. Yield: 0.11 g, 71%. IR (Nujol mull): 3330 w (vNH). 1H NMR (400.1 MHz, C6D6, 313 K): xcex4 7.94 (b.s, 8 H, o-Ph), 7.32 (b.s, 4 H, p-Ph), 7.07 (b.s, 8 H, m-Ph), 6.82 (b.s, Ph-tolyl), 6.46 (b.s, NH-tolyl), 2.36 (b.s, CH-PCP), 2.22 (b.s, CH3-tolyl), 0.24 (b.s, 18 H, CH3xe2x80x94SiMe3). 31P{1H} NMR (161.9 MHz, C6D6, 313 K): xcex4 22.2 (b.s). Analysis calculated for C38H47Cl2HfN3P2Si2: C, 49.97; H, 5.19; N, 4.60. Found: C, 49.76; H, 5.32; N, 4.50.
Preparation of ZrCl2{(C(NCy)NCy)C(Ph2Pxe2x95x90NSiMe3)2}
Solid dicyclohexylcarbodiimide (0.057 g, 0.28 mmol) was added to a stirred solution of [ZrCl2{C(Ph2Pxe2x95x90NSiMe3)2}] (0.20 g, 0.28 mmol) in 10 mL of toluene at room temperature. The white solid which precipitated immediately was isolated by filtration and redissolved in 10 mL of THF. This solution was layered with few mL of toluene for crystallization. After 2 days at xe2x88x9215xc2x0 C., colorless crystals were deposited which were again isolated by filtration. Yield: 0.27 g, 0.24 mmol, 86%. IR (Nujol mull): 1595 s (vCN), 1H NMR (400.1 MHz, C6D6, 298 K): xcex4 7.80 (m, 4 H, o-Ph) 7.46 (m, 8 H, m-Ph), 7.32 (m, 4 H, o-Ph), 7.20 (m, 4 H, p-Ph), 7.13-7.06 (m, 5 H, Ph-toluene), 3.92 (b.tt, 1 H, ipso-Cy), 3.65 (m, THF), 3.16 (b.tt, 1 H, ipso-Cy), 2.50 (b.dd, 2 H, p-Cy), 2.31 (s, 3 H, CH3-toluene), 2.18 (b.d, 2 H, o-Cy), 1.88 (b.d, 2 H, o-Cy), 1.70 (m, 2 H, o-Cy), 1.38 (m, 8 H, m-Cy), 0.91 (m, 2 H, o-Cy), 0.45 (b.dd, 2 H, p-Cy), 0.01 (s, 18 H, CH3xe2x80x94SiMe3). 13C {1H} NMR (100.6 MHz, C6D6, 298 K): xcex4 148.7 (b.t, 2JPC=4 Hz, quaternary Cxe2x80x94CNCy), 138.4 (s, 1C, ipso-toluene), 133.9 (m, o-Ph), 133.0 (m, ipso-Ph), 133.1 (s, p-Ph), 129.6 (s, o-toluene), 129.1 (t, 3JPC=6 Hz, m-Ph), 128.9 (s, m-toluene), 128.8 (t, 3JPC=6 Hz, m-Ph), 127.5 (m, ipso Ph), 126.0 (s, p-toluene), 59.5 (s, ipso-Cy), 57.5 (s, ipso-Cy), 34.8 (s, o-Cy), 30.9 (s, o-Cy), 27.4 (s, m-Cy), 27.3 (s, p-Cy), 27.2 (s, p-Cy), 25.8 (s, m-Cy), 21.6 (s, CH3-toluene), 15.5 (t, 1JPC=96.0 Hz, quaternary Cxe2x80x94PCP), 4.1 (s, CH3xe2x80x94SiMe3). 31P{1H} NMR (161.9 MHz, C6D6, 298K): xcex4 21.0 (s). Analysis calculated for C51H58Cl2N4P2Si2Zr: C, 60.21; H, 6.74; N, 5.51. Found: C, 59.95; H, 7.07; N, 5.66.
Polymerization Conditions and Results
In the examples, the pressures given are gauge pressures. The following abbreviations and terms are used:
Branching: reported as the number of methyl groups per 1000 methylene groups in the polymer. It is determined by FT-IR.
Polydispersity: weight average molecular weight (Mw) divided by number average molecular weight (Mn).
DSC: differential scanning calorimetry.
GPC: gel permeation chromatography.
MeOH: methanol.
PMAO-IP: a type of polymethylaluminoxane.
Anhydrous toluene was purchased from Aldrich and purified over molecular sieves prior to use. PMAO-IP was purchased from Akzo-Nobel and contained 13.5 weight % of Al. B(C6F5)3 was purchased from Boulder Scientific Inc. and used without further purification. [CPh3][B(C6F5)4] was purchased from Asahi Glass Inc.; lot #: 980224.
Polymer molecular weights and molecular weight distributions were measured by GPC (Waters 150-C) at 140xc2x0 C. in 1,2,4-trichlorobenzene calibrated using polyethylene standards.
FT-IR was conducted on a Nicolet Model 750 Magna IR spectrometer.
DSC was conducted on a DSC 220 C from Seiko Instruments. The heating rate is 10xc2x0 C./minute from 0 to 200xc2x0 C.
Part A: Solution Phase Polymerization
All the solution polymerization experiments described below were conducted using an Autoclave Engineers Zipperclave reactor (500 mL). All the chemicals (solvent, catalyst and cocatalyst) were fed into the reactor batchwise except ethylene which was fed on demand. No product was removed during the polymerization reaction. As are known to those skilled in the art, all the feed streams were purified prior to feeding into the reactor by contact with various absorption media to remove catalysts killing impurities such as water, oxygen, sulfur and polar materials. All components were stored and manipulated under an atmosphere of purified argon or nitrogen. The reactor uses a programmable logical control (PLC) system with Wonderware 5.1 software for the process control. Ethylene polymerizations were performed in the reactor equipped with an air driven stirrer and an automatic temperature control system.
The catalyst was dissolved in toluene. Polymerization temperature is as indicated in the table below. The polymerization reaction time is typically 10 minutes. The reaction was terminated by adding 5 mL of methanol to the reactor and the polymer was recovered by evaporation of the solvent. The polymerization activities were calculated based on the ethylene consumption.